Method of raising liquids



March 31, 1925.

R. REDMANN METHOD oF'Rusme LIQUIDS Fiied Dee. 15,- 1923 2 Sheets-Sheet 1 March 31. 1925'. 1",s31,s7o

R. REDMANN 4 ETHOD OF RAISING LIQUIDS Filed. el 15, 1923 2 Sheets-Sheet 2 Patented Mar. 31, 1925.

UNITED STATES RUDOLF REDMANN, 0F NUREMBEBG, GERMANY.

METHOD OF RAISING LIQUIDS.

Application filed. December 15, 1923. Serial No. 680,918.

T0 aZZ whom it may concern:

Be it known that I, RUnoLr REDMANN, a citizen of German Republic, residing at Nuremberg, Germany, have invented cer tain new and useful Improvements in Methods of Raising Liquids, of which the following is a specification.

This invention relates to the problem of raising liquids with the aid of a slight vacuum to comparatively great delivery heads, for instance to feed fuel to the engine of motor vehicles from a reservoir situated in the lower part of the vehicle.

In the suction plants for fuel and in the automatic suction carburetors of known type, especially for motor vehicles, the effec tive sucking of fuel from the lower reservoir into the suction device is always dependent on the actual suction force at disposal in the suction pipe'of the engine and on the suction head to be overcome.

It has been found in many cases that at the maximum speed of the vehicle and when running up inclines no fuel was delivered so that finally it was impossible to continue the travel. This was due to the fact that with a suction force, which with an open throttle valve in the suction tube amounted to only about 4 cmsamercury column, it was impossible to overcome a suction head of l m. (which at the climbing of a hill of 18% upward slope increases to 1.5 m.). In order to raise a fuel column of l m. to 1.5 in. a suction force of 6 cms. to 10 cms. inercury column ought to be available. As this is not the case a more or less voluminous collecting reservoir was fixed on the dash wall to avoid this inconvenience with the vacuum fuel raiser, so that in the above mentioned case the carburetor could befed from this collecting reservoir. The fuel in this collecting reservoir was however soon exhausted at hill climbing and when running at maximum speed. It is of importance to avoid this inconvenience, and the more so as, with the great size of the vacuum fuel raiser, used at present, the cost of manufacture is very high, and as it is further sometimes impossible to accommodate the collecting reservoir on the dash board.

This invention has for its object to create a new method foravoiding the above men tioned inconveniences. This method consists in that a limited length of the liquid column is separated by admission of a higher pressure (for instance atmospheric pressure) from the liquid coluinnraised by the vacuum. This separated" part is raised between the two fluid pressures into a collector inserted in the suction conduit. In order to make the raising automatic the admission of the higher pressure is, according to the invention, automatically controlled from the liquid level in the collector.

The invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawings forming a part of this specification, with the understanding that while on the drawings several embodiments of an arrangement adapted for the carrying out of the method are disclosed,

the invention is not confined to any strict invention. I

Figs. 2 and 2* show constructional modifications of this second embodiment.

Fig. 3 shows the third invention.

Fig. 4 shows a special construction of the fuel conduit between the collector and the carburetor. Figs. 5, 5 5*, 5, 5 illustrate the different manners of inserting the pipe conduit into the fuel reservoir.

- Fig. 6 showsa modification of arrangement shown in Fig. 3.

Fig. 7 illustrates a special construction of the vertical part' of the suction tube.

In the form of construction shown in Fig. 1 the collector built into the suction conduit is arranged in the form of the communi the valve Fig. 2 shows a second embodiment ofthe embodiment of the i eating tubes a, b. Thetubular arm a is .en-

larged at the upper end to form a reservoir in which a float a is located. The arm a is connected at the lower endby a tube f with the carburetor B, a check valve .9 preventing the fuel being sucked back from the carburetor to the collector. Into the other end of the tubular arm aa vacuumtube 9 opens which terminates at the other end in the suction tube of the engine so that when the engine is running there is in this tube 9 a pressure permanently below the atmospheric. With the upper part of the tubular arm a a suction tube is also connected. The tubular arm I) of the collector is connected atthe upper end with the atmosphere. A pressure tube d adapted to be shut off from the tubular arm b and'consequently from the atmosphere by means of a valve, terminates also in the tubular arm I) of the collector. The valve h in the tubular arm 6 is connected by a system of levers with the float a in the tubular arm a in such a manner that when the fuel level is low the valve 'h closes, being however opened when the fuel level A tube 6 which dips into the fuel reservoir A branches off to the suction tube 0 and the pressure tube (Z at a short distance above the fuel reservoir. I

The operation of this apparatus is as fol- I ,lowszBefore starting, the collector a, b is filled with fuel approximately up to half its height. When the engine starts the fuel begins to rise through the suction force of the engine from the reservoir suction tube 0. The liquid fuel in the collector is at the same time sucked off from the tubular arm 7) over into the tubular arm a so that the float a is thoroughly raised until the valve h is opened. At this instant air under atmospheric pressure flows through the pressure tube d to the point at which tube 0 branches oft, whereby the column of fuel in the suction tube 0 is cut off from the reservoir A, The fuel in tube 6 flows back to the reservoir and the column of fuel in the suction tube 0 enclosed between the vacuum and the pushing atmospheric pressure rises until it flows into the collector a. The vacuum in the collector is almost completely destroyed by the infiowing air so that the fuel flows either back into the tubular arm I) or to the carburetor. When the float has reached its lowest position it strikes stop 1 on rod 2 and shuts off the pressure tube from the atmosphere by closing the valve h'so that the suction begins again.

Valve it will however be opened only when the rising fuel level has reached point a in Fig. 1. The height 09 must be greater than the height w in order that the plant can operate correctly; The modification shown in Fig. 1 serves to reduce the height a? to the minimum value. In thiscase the tubular arm 6 and not the pressure pipe d, is directly shut offby the valve 71. This valve arrangement might also be used in connectionwith the form of construction in Fig. 1. The lower part of the collector is enlargedto form a reservoir into which the tubular arm (0 projects for a short distance. In order to prevent the fuel being completely sucked out of the lower reservoir at one suction period a..valve a is arranged to close the tubular A into tube 6 and arm a as soon as the float opens the valve 7b.

The operation is in principle the same as in arm into the other tubular arm when the fuel rising from the reservoir reaches the point at which the suction tube 0 and the pressure tube (Z meet.

In the form of construction shown in Fig. 2 the collector is constructed like a simple air-tight reservoir 76; the pressure tube (Z has. preferably at a point below the collector, a U-shaped bend i which communicates at the pressure side with the atmosphere and is filled with a. liquid up to a determined height so that the float, dipping hell or the like, when at its highest position, shuts off from the atmosphere the pressure tube d in the direction of the fuel reservoir by means of a valve h. The bend i may be enlarged to form a reservoir. Before starting'the collector is has to be filled up to quarter capacity with fuel. When the engine is started the fuel rises, owing to the sucking action of the engine, from the reservoir in the suction pipe 6, c and from the auxiliary reservoir '5 in the pressure pipe d until the float opens by its weight the valve h, and the same functioning occurs again as has already been described with reference to Fig. 1. In bend i there is such a quantity of fuel that the valve 71, opens only when the fuel in the suction tube 0 rises to a point equal to the distance a which is determined by the filling of the reservoir. The overflowing of the col lector 7c is impossible as the pressure tube 0 reaches almost to the bottom of the collector and as there is still a slight pressure below the atmospheric in said collector when this collector is filled to a determined measure.

which retains the column of liquid sucked into the pressure tube (i so that the valve h does not shut off the pressure tube d. The

delivery can therefore continue only when the carburetor has consumed suific1ent fuel so that the fuel column above the or1fice of the suction tube 0 and the vacuum above the same.

have sunk to such an amount that. the raised liquid column goes farther back in the pressure tube (2 until thevalve h closes again and the suction period begins again.

This form of construction of the fuel suction plant presents the great advantage that the bend i may be filled with any other liquid than benzol, for instance with water or'glyc erine, etc., so that instead' of a metal float a cork float can be used which will never become leaky. It is a veryawell known fact that benzol dissolves any material with which cork floats may be impregnated. I

The height a: must in this case be at least 5 centimeters greater than the height w. The suction force of the engine is not constant with such plants but may vary within wide limits according to the amplitude for which the throttling valve opens, for instance between 4: to 40 centimeters of mercury column. According to the invention the regulated action of the fuel raiser might be disturbed by these fluctuations. It is therefore advisable to mount in the vacuum tube 9 a compensating valve which maintains the vacuum constant.

The form of construction shown in Fig.-

2 is similar to that shown in Fig. 2 with the difference however that the valve it does not directly shut oft from the outer air the pressure tube cl but the reservoir 2', from which it results that the liquid from the reservoir 2' is sucked up into the tube (Z only when the rising fuel column from the main reservoir has reached the point at which the two tubes 0 and (Z join. Inversely the liquid column which has been raised in the pressure tube (Z must fall back almostentirely to the original position before the valve it closes again. The supply pipe 0 needs therefore to extend into the fuel in the reservoir 74 only for a few centimeters in order to prevent the excessive filling of the reservoir its height can therefore be only very short. If the height 00 has to be reduced a valve 2 is, further arranged in the reservoir 2' which closes as soon as valve In Fig. 3 another embodiment of the in-- vention is shown. In this case the collector Z arranged above the carburetor has an air valve 0 or a suction valve and it isconnected with the air-tight reservoir, situated lower than the collector, by two tubes m and n. The tube on is connected with the pressure pipe of the reservoir and the supply pipe 77 with the bottom of the reservoir. The supply pipe 72 is connected in proximity to the reservoir with the atmosphere by a vertical stand pipe. The tube a has to be placed in such a manner that the fuel flows from the reservoir under natural head so that the tube can take in a determined quantity of fuel. The collector Z has to be filled with fuel before the starting until the valve 0 opens. lVhen the motor has been started and the carburetor has consumed a sufficient quantity of fuel the fioat descends by leaps until the valve 0 closes. At this instant, owing to the suction force of the engine, the fuel which during the outflow period from the reservoir has flowed into the delivering pipe rises into the collector Z. The vacuum in the collector Z is almost completely destroyed by the inflowing air and the air valve 0 is relieved so that it is opened by the pressure of the float. The outflow period begins now again. During the suct-ionperiod the fuel is pi'evented'fi'oin flowing out of the reservoir by the pressure below atmospheric in the tube m. A check-valve p prevents the rising of fuel in the tube m. In all forms of construction the buoyance of the float must be so low, in order to ensure the in How of air behind the fuel column to be raised, that the valve 0 cannot prematurely open when the raisedfuelcolumn arrives.

in the collector and the atmospheric air has flowed in through the tube. Itniay be advisable to enlarge the suction tube it directly below the reservoir to form a reservoir into which the air inlet tube enters from above.

Fig. 4 shows a special form of construction of the collector adapted tobe used in connection with all forms of construction of the fuel delivering device. The collector r is in this case directly connected with'the carburetor by an open tube so that the check valve 8- (Fig. 1) is omitted. The height of construction 1 of the fuel tube between collector and carburetor is' 'however made so great that, even when climbing the steepest hill, the vacuum in the collector ris not capable of raising thefuel column in this tube. Thisarrangement presents the advantage that even during the suction period fuel can fiow directly from the collector to the carburetor. This arrangement can be preferably used in combination with the ar rangement shown in Fig. 7 which will be hereinafter described.

The form .of construction shown in F 5 represents a most favorable arrangement of the pressure and suction tubes of the type shown in and described with regard to Figs. 1 and 2. The tube 6 is connected with the riser of the reservoir from which the air has been evacuated, andit branches off into the suction pipe 0 and pressure pipe cl in close proximity tosaid reservoir. The.

suction tube 0 is at first for a distance t approximately horizontal or, which would be even better, slightly inclined to the direc tion of travel to ascend in vertical directionv preferably under the rear mud-guard of the motor vehicle to continue 'onlythen under the carriage frame up to the dash wall. The distances 2 and u are of such lengthsthat a fuel column. (of the length t+u) can be raised into the collector by the least suction force which is at disposal.

When the valve is arranged in the manner shown in Figs. 1 and 2 the length it must correspond at least to the height of the reservoir.

The arrangement shown in Fig. 5 is fundamentally the same as that shown in Fig. 5-

With the exception that the tube 6 terminates in the bottom plate of the reservoir which is closed air-tight, the air being discharged only through the riser. The tube 6 branches off only above the lower orifice of the riser to form the pressure tube cl and the suction tube 6. In this arrangement thelevel of the fuel in the tank has no influence upon. the fuel which has been actually raised in the suction pipe even if the valve 72. is arranged in accordance with Figs. 1 and 2.- In this case it is advisable, just as with the construction shown in Fig. 5, to enlarge the tube 6 slightly at the point where the tube 0 branches off. The Figs. 5*, 5, 5 show further arrangements of the tubes m and n with the use of the collector shown in and described with reference to Fig. 3. In this case a determined quantity of fuel is raised in the equalization tube on simultaneously with each suction period so that the quantity of fuel which has to be raised into the collector at each suction period is forced at each outflow period by the raised fuel column in the equalization tube on from the reservoir into thedelivering tube a.

In the form of construction shown in Fig. 5 the tube connections are similar to those shown in Fig. 3 but the check valve 79 is omitted. In Fig. 5 the suction tube a is connected with the second riser of the reser voir. In Fig. 5 the tube a terminates in the bottom of the reservoir. In all three arrangements of the tubular conduits the tube m is preferably arranged so that it ascends behind the rear mud guard, the distance if being of the same length as describedwith reference to Fig. 5 for the tube 0.

The collector shownin Fig. 6 may be substituted for the collector Z of Fig. 8 when the tube arrangements according to Figs. 5 to 5 have to be utilized. This collector has no air inlet valve but only a valve 4) which shuts off the suction tube 9 after each suction period and releases the same after each outflow period. The pressure below-atmospheric is destroyed in this case by the inflowing air after a fuel charge has been raised into the collector.

InFig. 7 a special arrangement for the suction tube or delivering tube 0 or a is shown which presents special advantages. In this case the suction pipe is a serpentine pipe, especially the vertical part of the same,

or it is upwardly inclined so that the quantity of fuel to be raised each time may be increased at will, the delivery head or the vertical height 9 of the fuel column in the serpentine remaining always approximately equal in opposition to what happens in a normal vertical suction pipe.

I claim l. The method of raising liquids from a reservoir toa collector at a substantial head above such reservoir, by means of a vacuum, comprising raising a column of liquid by said vacuum, separating a length of, said liquid by air admitted through means controlled by the fuel level'in said collector, and raising such separated length by the vacuum.

2. In an apparatus for raising liquids, the combination of a liquid reservoir, an evacuating means, a liquid collector above the level of said reservoir, a suction tube leading from said reservoir and having two branches connected with said collector, one of said branches being connected to the evacuating means and the other of saidbranches being adapted to have the suction therein temporarily relieved.

3. In an apparatus for raising liquids, the

combination of a liquid reservoir, a liquid collector above the level of said reservoir, an evacuating means, a float in said collector, a suction tube leading from said reser voir to said collector, and connected to said evacuating means, and a valve operatively connected to said float, said valve being adapted to admit air to said suction tube.

4. In an apparatus for raising liquids, the combination of .aliquid reservoir, a liquid collector above the level of said reservoir, an evacuating means connected to said collector, a suction pipe leading from the bottom of said reservoir to said collector, a metering stand-pipe branched from said suction tube and opening to the air at a point above the liquid level of said reservoir, a I

second pipe leading from the vacuum space of sald collector and opening 1nto said reservoir, and a fioat controlled valve on said collector to open said collector to the atmosphere at a predetermined high liquid level and to close such communication at .a predetermined low liquid level.

5. Apparatus according to claim 2 in which the suction pipe has its vertical portion formed as a serpentine.

In testimony whereof I afiix ture. I

RUDOLF REDMANN.

my signa- WVitnesses PAUL DREY, ELSIE BAER. 

